一個april beacon里攜帶的信息如下

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1	<code class=" hljs ">0201061AFF4C0002159069BDB88C11416BAC3F33468C2788A3044B0378C60C09417072696C426561636F6E051250002003020A0000000000000000000000</code>

具體是什么意思呢

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<code class=" hljs vhdl">02? Number of bytes that follow in first AD structure 01? Flags AD type 06 ????Flags value 0x1A = 000011010 ???????bit 0 (OFF) LE Limited Discoverable Mode ???????bit 1 (ON) LE General Discoverable Mode ???????bit 2 (OFF) BR/EDR Not Supported ???????bit 3 (ON) Simultaneous LE and BR/EDR to Same Device Capable (controller) ???????bit 4 (ON) Simultaneous LE and BR/EDR to Same Device Capable (Host) 1a Number of bytes that follow in second (and last) AD structure 前面是常規智能硬件廣播包部分 ff （FF代表后面是Manufacture Data） 4c 00?? (組織標識，0x4c00蘋果公司標識,https://www.bluetooth.org/en-us/specification/assigned-numbers/company-identifiers) 02 （0x02 ibeacon標識位） 15 （0x15,22個字節標識長度，uuid，major，minor總和的長度） 90 69 bd b8-8c 11-41 6b-ac 3f-33 46 8c 27 88 a3 (Proximity UUID) 04 4b(1099，major) 03 78(888，minor) c6? （切記這里是補碼，轉化為原碼就是-58，iBeacon的信號發出強度值，用來作為和RSSI一起測距的基準 ，txPower） ????????計算 ????????????C6 ????????????1100 0110 補碼 ????????????1100 0101 反碼 ????????????1011 1010 原碼 ????????????-（32+16+8+2） ????????????-58 0c09??? （未知） 417072696c426561636f6e（AprilBeacon字符串對應的十六進制） 051250002003020a0000000000000000000000（未知） </code>

Proximity UUID ：這是將你所有的beacon與其他人的beacon設備區別開的id！例如，目前在商店里某個區域分布著多個beacon形成一條“鏈帶”，用于為顧客提供特定的服務，那么歸屬于同一條“鏈帶”的beacon將分配到相同的proximity UUID。為這條“鏈帶”設計的專用應用程序將會在后臺使用這個UUID掃描到這條“鏈帶”中的beacon設備。

major 編號：用于將相關的beacon標識為一組。例如，一個商店中的所有beacon將會分配到相同的major編號。通過這種方式，應用程序就能夠知道顧客位于哪一家商店。

minor 標號：用于標識特定的beacon設備。例如一個商店中的每一個beacon設備都擁有唯一的minor編號，這樣你才能夠知道顧客位于商店中的哪個位置。

Measuring distance（測量距離）?
最后一個值， TX power ，用于確定你和beacon之間距離有多近。根據這個值不但可以獲得粗略的信息（比如靠近/遠離/不在范圍內等），也可以獲取精確到米的距離（當然你也可以轉換為以步為單位的距離）。那么如何實現？

TX power （上面例子中為0xC6=198，根據2的補碼測得256-198=-58dBm）是距離設備1米測得的信號強度值（RSSI- Received Signal Strength Indication，接收到的信號強弱指標）。假如接收到的信號強度減弱了，那么我們可能在遠離。只要知道1米距離的RSSI，以及當前的RSSI（我們可以從接收到的信號中一塊獲取到這些信息），那么計算出當前的距離是可能的。IOS已經實現了個這個功能，對于其它平臺需要自己手動編碼計算 。

一個簡單的測距函數

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<code class="language-java hljs ">protected static double calculateAccuracy(int txPower, double rssi) { ????????if (rssi == 0) { ????????????return -1.0; // if we cannot determine accuracy, return -1. ????????} ????????double ratio = rssi * 1.0 / txPower; ????????if (ratio < 1.0) { ????????????return Math.pow(ratio, 10); ????????} else { ????????????double accuracy = (0.89976) * Math.pow(ratio, 7.7095) + 0.111; ????????????return accuracy; ????????} ????}</code>

在使用藍牙時需要加權限

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<code class="language-xml hljs "> <uses-permission android:name="android.permission.BLUETOOTH"> ????<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"> ????<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"> </uses-permission></uses-permission></uses-permission></code>

關鍵代碼如下

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<code class="language-java hljs ">package cn.edu.zafu.ble; import android.app.Activity; import android.bluetooth.BluetoothAdapter; import android.bluetooth.BluetoothDevice; import android.bluetooth.BluetoothManager; import android.content.Context; import android.content.Intent; import android.os.Bundle; import android.util.Log; public class MainActivity extends Activity { ????private BluetoothAdapter mBluetoothAdapter; ????@Override ????protected void onCreate(Bundle savedInstanceState) { ????????super.onCreate(savedInstanceState); ????????setContentView(R.layout.activity_main); ????????BluetoothManager bluetoothManager = (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE); ????????mBluetoothAdapter = bluetoothManager.getAdapter(); ????????if (mBluetoothAdapter == null || !mBluetoothAdapter.isEnabled()) { ????????????Intent enableBluetooth = new Intent( ????????????????????BluetoothAdapter.ACTION_REQUEST_ENABLE); ????????????startActivityForResult(enableBluetooth, 1); ????????} ????????mBluetoothAdapter.startLeScan(mLeScanCallback); ????} ????private BluetoothAdapter.LeScanCallback mLeScanCallback = new BluetoothAdapter.LeScanCallback() { ????????@Override ????????public void onLeScan(final BluetoothDevice device, final int rssi, ????????????????final byte[] scanRecord) { ????????????int startByte = 2; ????????????boolean patternFound = false; ????????????// 尋找ibeacon ????????????while (startByte <= 5) { ????????????????if (((int) scanRecord[startByte + 2] & 0xff) == 0x02 && // Identifies ????????????????????????????????????????????????????????????????????????// an ????????????????????????????????????????????????????????????????????????// iBeacon ????????????????????????((int) scanRecord[startByte + 3] & 0xff) == 0x15) { // Identifies ????????????????????????????????????????????????????????????????????????????// correct ????????????????????????????????????????????????????????????????????????????// data ????????????????????????????????????????????????????????????????????????????// length ????????????????????patternFound = true; ????????????????????break; ????????????????} ????????????????startByte++; ????????????} ????????????// 如果找到了的話 ????????????if (patternFound) { ????????????????// 轉換為16進制 ????????????????byte[] uuidBytes = new byte[16]; ????????????????System.arraycopy(scanRecord, startByte + 4, uuidBytes, 0, 16); ????????????????String hexString = bytesToHex(uuidBytes); ????????????????// ibeacon的UUID值 ????????????????String uuid = hexString.substring(0, 8) + "-" ????????????????????????+ hexString.substring(8, 12) + "-" ????????????????????????+ hexString.substring(12, 16) + "-" ????????????????????????+ hexString.substring(16, 20) + "-" ????????????????????????+ hexString.substring(20, 32); ????????????????// ibeacon的Major值 ????????????????int major = (scanRecord[startByte + 20] & 0xff) * 0x100 ????????????????????????+ (scanRecord[startByte + 21] & 0xff); ????????????????// ibeacon的Minor值 ????????????????int minor = (scanRecord[startByte + 22] & 0xff) * 0x100 ????????????????????????+ (scanRecord[startByte + 23] & 0xff); ????????????????String ibeaconName = device.getName(); ????????????????String mac = device.getAddress(); ????????????????int txPower = (scanRecord[startByte + 24]); ????????????????Log.d("BLE",bytesToHex(scanRecord)); ????????????????Log.d("BLE", "Name：" + ibeaconName + "\nMac：" + mac ????????????????????????+ " \nUUID：" + uuid + "\nMajor：" + major + "\nMinor：" ????????????????????????+ minor + "\nTxPower：" + txPower + "\nrssi：" + rssi); ????????????????Log.d("BLE","distance："+calculateAccuracy(txPower,rssi)); ????????????} ????????} ????}; ????static final char[] hexArray = "0123456789ABCDEF".toCharArray(); ????private static String bytesToHex(byte[] bytes) { ????????char[] hexChars = new char[bytes.length * 2]; ????????for (int j = 0; j < bytes.length; j++) { ????????????int v = bytes[j] & 0xFF; ????????????hexChars[j * 2] = hexArray[v >>> 4]; ????????????hexChars[j * 2 + 1] = hexArray[v & 0x0F]; ????????} ????????return new String(hexChars); ????} ????protected static double calculateAccuracy(int txPower, double rssi) { ????????if (rssi == 0) { ????????????return -1.0; // if we cannot determine accuracy, return -1. ????????} ????????double ratio = rssi * 1.0 / txPower; ????????if (ratio < 1.0) { ????????????return Math.pow(ratio, 10); ????????} else { ????????????double accuracy = (0.89976) * Math.pow(ratio, 7.7095) + 0.111; ????????????return accuracy; ????????} ????} } </code>

至此，本文也就結束，所謂初步，就是獲取ibeacon模塊的基本信息。

源碼下載?
http://download.csdn.net/detail/sbsujjbcy/8503507

轉載于:https://www.cnblogs.com/Free-Thinker/p/5560433.html

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